An active filter with inductive storage for compensation of inactive power of a rectifier with a capacitive filter

Abstract

Compensation of the inactive components of network current of a rectifier with a capacitive filter or a combination thereof under connection of a parallel active filter with inductive storage based on a current inverter is considered. The active filter allows increasing the power coefficient to the maximum values, and this result may be achieved at high values of storage inductance. Modeling of the “rectifier–active filter” system is carried out by spectral methods. It is shown that correction of the switching algorithm by storage-current feedback provides a decrease by three to four times of inductance at the same values of the power factor of the “rectifier–active filter” system. A multistage active filter consisting of a current inverter and voltage inverter with current stabilization on the direct current is proposed. The total cost for the inductive elements in the multistage active filter may reduced by one order with the same values of power factors. Comparison of voltage inverters based on bridge and half-bridge schemes is carried out. Advantages of half-bridge inverters are shown.